Fireproof shutter



April ,2, 1929. D 1,707,287

FIREPROOF SHUTTER Filed Aug. 30, 1926 fill Patented Apr. 2, 1929.

UNITED STATES TOMITARO SUDZKI, OF TOKYO-EU, JAPAN.

FIREPROOF SHUTTER.

Application filed August 30, 1926. Serial No. 132,598.

of Fig. 1. Ii shown in the drawing, each slat consis of outer and inner plates hav space left between them. The outer plate has its upper and lower edges 3, bent so as to form a channel at almost a right angle with the curved surface, edges gradually approaching each other. The ends of these edges are curled to make interlocking flanges as in The in nor plate bent to form a channel which tightly fits into the bent portions (3) (4) of the outer plate, the upper and lower edges 7, 8 being bent at almost a right angle with the curved surface, the distance between them gradually diverging.

As stated above, the outer plate (1) being in a shape of trapezoidal channel spreading at the bottom, and the inner plate also in the sonic shape but narrowing at the botton'i, they will be tightly .inti-zrloch'ed with each other and iiorrn a hollow slat it the latter is slipped into the former from its one end and then the bent portions oi the outer plate are pressed on the bent portions 7) (8) of the inner plate. Thus, the inner plate does not separate from the outer i" it i 1 Y reg plate, even it not connected to the latter by riveting or like means. However, in this shutterlike an ordinary one, it is necessary to attach an end lock or shield to both ends to prevent lateral movement of each slat, so that it is advisable to ensure the connection of the outer and inner plates still more terlocking joint. Its body (10) is provided with a tubular projection (11), the height of which is made equal to the width of space between the slats, namely a space between the outer and inner plates. The rivet (12) that passes through the said projection to connect the said. end. lock with the slats is used also for connecting the two plates. The outer surface of the end lock is made convex at as (13) to enable the slats to move up and down smoothly along rails. The air space between the outer and inner plates is intended for the prevention of heat ef- .iectively, and this space may sometimes be filled with heat insulating materials. The shutter of my invention is very effective against fire and can be rolled up around a shaft without dilliculty. Besides, it can be 1nanulactured easily. An ordinary slat consists oil a surface carving gradually between upper and lower interlocking flanges, while in this invention these flanges being bent at almost the right angle with the curved surface as in (S) (4:), the slat is more rigid.

Claims:

1. A fire-proof shutter consisting of slats jointed together, each slat comprising outer and inner plates having space left between them, both plates being bent obliquely at the upper and lower edges to form a channel having widened bottom and a channel having widened top respectively .and interlocked with iaeh other, both plates having air space between them, the edges of the ohter plate being extended laterally and curved whereby to be jointed to the correspondingly shaped edge oli an adjacent slat of the shutter.

2. A fire-proof shutter consisting of slats jointed together, each slat comprising outer and inner plates having space left between them, both plates being bent obliquely at the upper and lower edges to form a channel having widened bottom and a channel having widened top respectively and interlocked with each other, the edges of the outer plate being extended laterally and curved whereby to be jointed to the correspondingly shaped edge of an adjacent slat of the shutter. V

In testimony whereof I have affixed my signature. TOMITARO SUDZKI. 

